This invention relates generally to apparatus for automatically gluing objects. More particularly, the instant invention is related to apparatus for automatically gluing an object in response to predetermined movement of same.
In the prior art a variety of apparatus has been employed to automatically glue strips of paper or other objects during automated handling of same. For example, spray-type gluers have been associated with printing machines in the prior art. One disadvantage of machines of this character is that usually too large an area is sprayed by the gluer often resulting in contamination of the conveying apparatus utilized to move the glued objects through the mechanized process. Often spray gluing apparatus becomes jammed as deposits of glue form and dry on the output orifice. Often conventional spray heads are too big or cumbersome to fit between the rollers employed in conventional folding machines and are usually too big to be employed in conjunction with apparatus for printing small magazine or newspaper inserts.
Another type of prior art gluing apparatus simply wipes on glue in the form of a strip during the conveying of an object to be glued through a mechanized process. One problem with this technique is that glue often leaks down the front edge of inserts, and when the papers or other objects are subsequently stacked, the inserts will stick together. A prior art glue dispenser of this nature usually includes a head having a downwardly pointing wiping orifice which contacts the slidably moving object to be glued. Wiping-type glue dispensers of this nature are controlled by a remotely located shut-off valve above the apparatus which can be manipulated to control the flow of glue. However, a problem with apparatus of this nature is that glue often continues to drip or run out of the applicator, eventually jamming the feed machinery. When the glue leaks onto the fold rollers of a folding machine the machine must be stopped so that rollers can be cleaned appropriately, obviously slowing down production. In order to overcome the latter problem, it has been known in the fold rolling art to provide a circumferential groove in the fold rollers to avoid mechanical contact with the strip of glue applied to the conveyed objects. The strip will normally line up with the roller groove to prevent contact, but deviation from ordinary roller alignment present problems. Of course grooved rollers must be changed where not suited for other jobs with which the rolling machine may be employed.